Originally Posted by jford
As long as I can remember, BIAB/RB has never properly supported an add2 or a sus2 chord. As has been stated, sometimes you get the "3" (an add2 chord) and sometimes you don't (a sus2 chord). Also, the A2 designation is used whether it's an add2 or add9 (the octave being the difference, but BIAB doesn't differentiate).
The problem often comes down to MIDI vs RealTrack. With MIDI styles we're usually able to handle every chord, since MIDI notes can be added or moved or changed easily, but with RealTracks we're stuck with whatever the musician recorded. Sometimes they don't record every single possible chord - this can be due to a number of factors, the most logical of which is whether it's possible to play such a chord (6 strings on a guitar can be quite limiting when a complex chord has more than 6 notes), and also whether such a chord is contextually appropriate for the genre (for example a C7susb9#11b13 may be useful for jazz but not so useful for punk rock). As well, data storage was a limiting factor not that long ago, and RealTracks from the early years may be missing some of the more complex chords in an effort to reduce bandwidth and storage space.

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